Process for breaking petroleum emulsions



Patented Oct. 16, 1934 UNITED STATES 'PROCESS FOR BREAKING PETROLEUMEMULSIONS Claudius H. M. Roberts, San Marino, Calit, as-

signor to Tretolite Company, Webster Groves, Mo., a corporation of NoDrawing. Application December 7, 1933,

Serial No. 701,345

15 Claims.

This invention relates to the treatment of emulsions of mineral oil andwater, such as petroleum emulsions, for the purpose of separating theoil from the water, my present application being a continuation in partof my pending application for Patent Serial No. 665,962, filed April 13,1933.

Petroleum emulsions are of the water-in-oil type, and comprise finedroplets of naturally-occurring waters or brines, dispersed in a more orless permanent state throughout the oil which constitutes the continuousphase of the emulsion. They are obtained from producing wells and fromthe bottom of oil storage tanks, and are commonly referred to as cutoil, roily oil, emulsified oil" and bottom settlings.

The object of my invention is to provide a novel and inexpensive processfor separating emulsions of the character referred to into theircomponent parts of oil and water or brine.

Briefly described, my process consists in subjecting a petroleumemulsion of the water-in-oil type to the action of a treating agent ordemulsifying agent of the kind hereinafter described, thereby causingthe emulsion to break down and separate into its component parts of oiland water or brine, when the emulsion is permitted to remain in aquiescent state after treatment, or is subjected to other equivalentseparatory procedure.

The treating agent or demulsifying agent used in my process consists ofa mixed ester of a polyhydric alcohol of the kind obtained when apolyhydric alcohol or derivative thereof is partially esterified by thereplacement of one or more of the alcoholiform hydroxyls by one or moremonobasic, detergent-forming, carboxy acid residues or derivativesthereof, and when, in addition thereto, one or more of the alcoholiformhydroxyls is also replaced by an aliphatic, polybasic, carboxy acidresidue.

Esters are obtained by reactions between alcohols, such as monohydric orpolyhydric alcohols, and acids including monobasic or polybasic carboxyacids. One mole of a polyhydric alcohol may be combined with two molesof a monocarboxy acid. One might employ one mole each of two differentcarboxy acids. In cases where such carboxy acids are difierent butcombined with the same polyhydric alcohol, one may refer to theresulting ester as a mixed ester. The treating agent contemplated by myprocess consists of a mixed ester in which one of the organic acidscombined with the polyhydric alcohol or residue 55 is derived fromnon-hydroxylated, detergentforming, monocarboxy acids. It is well knownthat non-hydroxylated fatty acids such as oleic acid, stearic acid,palmitic acid, linoleic acid, etc. combine with alkalis such as causticsoda. or caustic potash to form soaps or detergents. It is also knownthat non-hydroxylated, monocarboxy rosin acids, such as abietic acid,combine with alkalis to produce detergent material. Naph thenic acidsderived from petroleum are generally non-hydroxylated andmonocarboxylic, and they combine with alkalis to produce soap-likematerials or detergents. The expression nonhydroxylateddetergent-forming, monocarboxy acids refers to the type of materialsabove indicated. The polyhydric alcohol employed to produce the treatingagent used in my process must not only be combined with at least onemolecule of a non-hydroxylated, detergent-forming, monocarboxy acid, butit must also be combined with at least one molecule of an aliphaticpolybasic acid.

One may denote a polyhydric alcohol by the formula R.(OH) n, in which nrepresents the numeral two or more. An aliphatic, polybasic, carboxyacid may be denoted by the formula A'.(COOH)n, in which n represents thenumeral two or more. The non-hydroxylated, monocarboxy,detergent-forming acids herein contemplated may be represented by theformula DCOOH, in which D represents the characteristic hydrocarbonchain and COOH is the conventional carboxyl group.

If a trihydric alcohol such as glycerol is combined with a dibasic acid,such as succinic acid and also with the monocarboxy, detergent-formingacid such as oleic acid, so that complete esterification results, thenthe finished product may be expressed by theformula D.A.R., in which Ris the polyhydric alcohol residue, A is the polybasic acid residue, andD is the detergent-forming acid residue. D.A.R. represents a mixed esterof the kind contemplated for use as the treating agent of my process. Ifglycerol is replaced by a dihydric alcohol such as ethylene glycol, andif the glycol is first combined with oleic acid and then combined withsuccinic acid, it is obvious that a mixed acid ester must result,insofar that the mixed ester contains an uncombined carboxyl radical.Such a type of mixed ester may be designated by the formulaD.A.(COOH):R, in which formula the symbols have their previoussignificance, and t represents the numeral one or more. If glycerol isreplaced by diglycerol, which is'essentially an ether alcohol havingfour hydroxyls, and if a mole of oleic acid and a mole of 'succinic .isuowmg formula enmplete esterifica ester resiil tiinig .uid ccntiain afreei hydrml' 5 thfij fasten his typ represented; hr 5 ans in. on; such.reaction between oileiei acid; and; acne :hydroimli radical of siycemiand: aiso between one ear-boxy at succinic acid cf the iierniula; fDAKCreagenm empioyefi eister'a orzth ey may chairmen)! mmprecess may beneutr ajciii or; thermair i i Briefly; them; in; the, broadest sensethe, reagent in Ztreatiin g agent: contemplated; by pr sent. process:may be the niimerai zero or one i or: mere;

dicals imiay b es eem d; wi h Y Ii rming acid; suchas eieicacid,:stearie:acid,:pa1mi ic acid, abitii: acid; napiitheriici acid; :et:Itg isrinid er s pie? derivativeaoithfiscf acids; sue

emp m;

iolsi, as; may he as ea nydric alcohol; I

' ons may ems-1Q sasbsxy: acida s nous: alpi haticg :ipolyhasie i xam ls: lsuic cliiib acid; meters acid, malic acid, a'eo nitic acid; 2

tartaric acid, citric acid, fumaric acid, etc. Simple derivatives ofthese acids, such as the halogen derivatives, are as satisfactory as theallphatic polybasic acids themselves. Anhydrides of the acids are assuitable as' the acids themselves.

The manufacture of mixed esters is relatively simple. Generallyspeaking, the reagents are heated together under conditions which tendto remove the water formed as a result of esteriflca- ,tion. In someinstances the reagents are heated at a temperature higher than theboiling point of water. Sometimes esterification is carried on at atemperature lower than the boiling point of water, and a dried inert gasis passed through the mixed mass to eliminate any water which may beformed. Sometimes a catalyst, such as a trace of a mineral acid isadded. These processes are well known and have been employed in theproduction of synthetic fats, neutral gums, plasticizers, syntheticresins, perfume materials, flavoring mate- =1. inc-mace: 7

itiieiacidiciiydre'gencan be replaced eeui', v-i

, indicated i y i 1 753 1 3 3 DALKGGOHDEaRfiOiI-I a; i in :whicir :mrepresents propyl alcohols; :to: produce: The :aeidiehydrogeni mayremain: unneutralize The droxyi oi :the: carbon! may: be combined; withn amine by; eliminating a hydrogen: of the amine with f the:iSGDQ'J-Eliibll OIi 11161861118: OIi zwatera Pyridine may utilizedSrepiacie :83: cnnyeh cf ithe :kind

, eacted with in tailiic: water-soluble salts; sue

ts; as. is amine at; 5r t i injetathieasif" The; previnuslyi :dese

ribed these as viirozeh of: th

. nf fioriniilas .th r ac d ir Z:

as the acid hydrogen equivalent.

My preferred treating agent or demulsifying agent is produced byreacting oleic acid and glycerol so as to obtain mono-olein. One mole ofmono-olein (or 356 lbs.) is then reacted with one mole offinely-pulverized succinic acid (orf118 lbs.) at about 185 to 200 0.,with constant 'stirring, and with the passage of dried air untilesterification takes place between one hydroxyl of themono-olein and onecarboxyl of the succinic acid. The completeness of reaction can berecognized by titration of the residual free acidic hydrogen, due to theuncombined succinic acid. Said material may be indicated by the formulaD.A.COO.Z.R.OH, in which D is an oleic acid residue, A is a succinicacid residue, CO0 is a conventional carboxyl residue, R is a glycerolresidue and OH is a-conventional hydroxyl radical, and Z is the acidhydrogen equivalent.

The materials previously described need not be employed alone, as ademulsifying agent, but may be employed in conjunction with othersuitable demulsiflers, such as water softeners, modified fatty acids,oil-soluble or water-soluble petroleum sulfonic acids, substitutedaromatic sulfonic acids, dialkyl sulfo acids, substituted amine acidicbodies, etc., or the salts and' esters of the same or the like. One mayadd any suitable inert solvent or solvents to the reagent contemplated,particularly solvents which would lower the viscosity of the product andmake it more adaptable for use, such as kerosene, solvent naphtha,cresol, pine oil, ethyl alcohol, butyl alcohol, propyl alcohol, etc. Theclass of materials contemplated by my present process is related to thebroad class reduce the corresponding mammals; maniac! 5 hiclr arewater-soluble; The ammonium radical 5 :eiopper: S92E55; on salts;aluminum salts =zine salts, magnesium of materials mentioned in mypending application for patent Serial No. 665,962, filed April 13, 1933.

In practising my process, a treating agent or demulsifying agent of thekind above described may be brought in contact with the emulsion to betreated in any of the numerous way now employed in' the treatment ofpetroleum emulsions of the water-in-oil type with chemical demulsifyingagents, such, for example, as by introducing the treating agent into thewell in which the emulsion is produced, introducing the treating agentinto a conduit through which the emulsion detergent-forming acidresidue, A is an aliphatic,

' polybasic, carboxy acid residue, C is the conventional carboxylresidue, R is a polyhydric a1- cohol residue, OH is the conventionalhydroxyl radical, Z is a metallic atom, m represents the numeral zero,one or more, and t represents the numeral one or more.

3. A process for breaking a petroleum emulsion of the water-in-oil type,which consists in subjecting the emulsion to the action of a mixed esterof the type D.A.(COO.Z)tR-(OH)m, in which D is a non-hydroxylated,monocarboxy, deteris flowing, introducing the treating agent into\gent-forming acid residue,Ais an aliphatic, polya tank in which theemulsion is stored, or introducing the treating agent into a containerthat holds a sludge obtained from the bottom of an oil storage tank. Insome instances, it may be advisable to introduce the treating agent intoa producing well in such a way that it will become mixed' with water andoil that are emerging from the surrounding strata, before said water andoil enter the barrel of the well pump or the tubing up through whichsaid water and oil flow to the surface of the ground. After treatmentthe emulsion is allowed to stand in a quiescent state, usually in asettling tank, at a temperature varying from atmospheric temperature toabout 200 F., so as to permit the water or brine to separate from theoil, it being preferable to keep the temperature low enough so as toprevent the valuable constituents of the oil from volatilizing. Ifdesired, the treated emulsion may be acted upon by one or the other ofvarious kinds of apparatus now used in the operation of breakingpetroleum emulsions, such as homogenizers, hay tanks, gun barrels,filters, centrifuges, or electrical dehydrators.

The amount of treating agent on the anhydrous basis that is required tobreak the emulsion may vary from approximately 1 part of treating agentto 500 parts of emulsion, up to a ratio of 1 part of treating agent to20,000 parts of emulsion, depending upon the type or kind of emulsionbeing treated. In treating exceptionally refractory emulsions of thekind commonly referred to as tank bottoms or residual pit oils, theminimum ratio above referred to is often necessary, but in treatingfresh emulsions, i. e., emulsions that will yield readily to the actionof chemical demulsifying agents, the maximum ratio above mentioned willfrequently produce highly satisfactory results. For the averagepetroleum emulsion of the water-in-oil type a ratio of 1 part oftreating agent to 10,000 parts of emulsion will usually be found toproduce commercially satisfactory results.

Having thus described my invention, what I claim as new and desire tosecure by Letters Patent is:

1. A process for breaking a petroleum emulsion of the water-in-oil type,which consists in subjecting the emulsion to the action of a mixed esterof the type D.A.(COO.Z)mR.(OI-I)m, in which D is a non-hydroxylated,monocarboxy, detergentforming acid residue, A is an aliphatic,polybasic, carboxy acid residue, CO0 is the conventional carboxylresidue, R is a polyhydric alcohol residue, OH is the conventionalhydroxyl radical, Z is the acid hydrogen equivalent, and m representsthe numeral zero, one or more.

2. A process for breaking a petroleum emulsion of the water-in-oil type,which consists in subjecting the emulsion to the action of a mixed esterof the type D.A.(COOZMRAOHM, in which D is a non-hydroxylated,monocarboxy,

basic, carboxy acid residue, CO0 is the conventional carboxyl residue, Ris a polyhydric alcohol residue, OH is the conventional hydroxylradical, Z is a monohydric alcohol radical, m represents the numeralzero, one or more, and t represents the numeral one or more.

4. A process for breaking a petroleum emulsion of the water-in-oil type,which consists in subjecting the emulsion to the action of a mixed esterof the type D.A.(COOZ) tR-(OH) m, in which D is a non-hydroxylated,monocarboxy, detergent-forming acid residue, A is an aliphatic,polybasic, carboxy acid residue, CO0 is the conven tional carboxylresidue, R is a polyhydric alcohol residue, OH is the conventionalhydroxyl radical, Z is a basic amine residue, m represents the numeralzero, one or more, and t represents the numeral one or more.

5. A process for breaking a petroleum emulsion of the water-in-oil type,which consists in subjecting the emulsion to the action of a mixed acidester of the type D.A.(COO.H)tR, in which D is a non-hydroxylated,monocarboxy, detergentforming acid residue, A is an aliphatic,polybasic, carboxy acid residue, COOH is the conventional carboxylradical, R is a polyhydric alcohol residue, and t represents the numeralone or more.

6. A process for breaking a petroleum emulsion of the water-in-oil type,which consists in subjecting the emulsion to the action of a mixed basicesterof the type D.A.R.(OH), in which D is a non hydroxylated,monocarboxy, detergent forming acid residue, A is an aliphatic,polybasic, carboxy acid residue, OH is the conventional hydroxyl radicaland t represents the numeral one or more.

'7. A process for breaking a petroleum emulsion of the water-in-oiltype, which consists in subjecting the emulsion to the action of a mixedamphoteric ester of the type D.A.(COOH) tR.(OH) c in which D is anon-hydroxylated, monocarboxy, detergent-forming acid residue, A is analiphatic, polybasic, carboxy acid residue, COOH is the conventionalcarboxyl radical, R is a polyhydric alcohol residue, OH is theconventional hydroxyl radical and t represents the numeral one or more.

8. A process for breaking a petroleum emulsion of the water-in-oil type,which consists in subjecting the emulsion to the action of a mixed esterof the type D.A.(COOH) mR.(OI-I) m, in which D is a non-hydroxylated,monocarboxy, fatty acid residue, A is an aliphatic, polybasic, carboxyacid residue, COOH is the conventional carboxyl radical, R is apolyhydric alcohol residue, OH is the conventional hydroxyl radical andm represents the numeral zero, one or more.

9, A process for breaking a petroleum emulsion of the water-in-oil type,which consists in subjecting the emulsion to the action of a mixed esterof the type D.A.(COOH) mR.(OI-I) m, in which polybasic, carboxy acidresidue, COOH is the con-' ventional carboxyl radical, R is a polyhydricalcohol residue, OH is the conventional hydroxylradical and 111.represents the numeral zero, one or more. a

10. A process for breaking a-petroleum emulsion of the water-in-oiltype, which consists in subjecting the emulsion to the action of a mixedester of the type D.A.(COOH) mR.(OH)'m. which D is an abietic acidresidue, A 'isan alihatic, polybasic, carboxy acid residue, COOH is theconventional carboxyl radical, R is a polyhydric alcohol residue, OH isthe conventional hydroxyl radical and m represents the numeral zero, oneor more;

11. A process for breaking a petroleum emulsion of the water-in-oiltype, which consists in subjecting the emulsion to the action of a mixedester of the'type D.A.(COOH) aR.(OH) m, in which D is anon-hydroxylated, monocarboxy, detergent-forming acid residue, A isa-succinic acid residue, COOH is the conventional carbox'yl radi- .cal,R is a polyhydric alcohol residue, OH is the conventional hydroxylradical, m represents the numeral zero, one or more, and d representsthe numeral zero or one.

12. A process for breaking a petroleum emulsion of the water-in-oiltype, which consists in subjecting the emulsion to-the' action oi. amixed ester of the type D.A-(COOH)dR.(OH)m, in which D is an oleic acidresidue, A is a succinic acid residue, COOHKis. the conventionalcarboxyl radical, R is a polyhydric alcohol residue, OH is theconventional hydroxyl radical, m represents the numeral zero, one ormore, and (1 represents the numeral zero or one.

13.'A process for breaking a petroleum'emulsion oi! the waterin-oiltype, which consists in subjecting the emulsion to the action of a mixedester of the type D.A.(COOH)mR.(OH)m, in which Dis a non-hydroxylated,monocarboxy, detergent-forming acid residue, A is an aliphatic,polybasic, carboxy acid residue, COOH is the conventional carboxylradical, R is a glycerol residue, OH is the conventional hydroxylradical and m represents the numeral zero, one or more.

14. A process for breaking a petroleum emulsion of the water-in-oiltype, which consists in subjecting the emulsion to the action of a mixedester of the type D.A.(COOH)dR.(OH)m, in which D is an oleicacidresidue, A is a succinic acid residue, COOH is the conventionalcarboxyl radical, R is a polyhydric alcohol residue, OH is theconventional hydroxyl radical, m represents the numeral zero, one ormore, and d represents the numeral zero or one.

15. A process for breaking a petroleum emulsion of the water-in-oiltype, which consists in subjecting the emulsion to the action of ademulsifying agent obtained by reaction between a mole of mono-olein andone carboxyl of a mole of succinic acid.

CLAUDIUS' H. M. ROBERTS.

